System and method for leveling an agricultural implement

ABSTRACT

A system includes an agricultural implement, a sensor, and a control system. The agricultural implement is configured to be coupled to an agricultural vehicle. The sensor is coupled to the agricultural implement and configured to output a signal indicative of a pitch angle of the agricultural implement. The control system is configured to receive the signal indicative of the pitch angle from the sensor, determine whether the pitch angle is within a pitch angle range, generate a hitch height control signal indicative of instructions to adjust a hitch actuator if the pitch angle is not within the pitch angle range, and communicate the hitch height control signal.

BACKGROUND

The present disclosure relates generally to agricultural implements, andmore specifically to leveling an agricultural implement coupled to anagricultural vehicle.

An agricultural implement may be coupled to a tractor or otheragricultural vehicle to perform an agricultural task (e.g., tilling,planting, seeding, spraying, fertilizing, harvesting, etc.). Theimplement may be towed behind the tractor or mounted to the tractor.During the performance of an agricultural task, the implement may tiltrelative to the field, resulting in poor performance and reducedefficiency.

BRIEF DESCRIPTION

Certain embodiments commensurate in scope with the originally claimedsubject matter are summarized below. These embodiments are not intendedto limit the scope of the claimed subject matter, but rather theseembodiments are intended only to provide a brief summary of possibleforms of the disclosure. Indeed, the disclosure may encompass a varietyof forms that may be similar to or different from the embodiments setforth below.

In one embodiment, a system includes an agricultural implement, asensor, and a control system. The agricultural implement is configuredto be coupled to an agricultural vehicle. The sensor is coupled to theagricultural implement and configured to output a signal indicative ofan implement pitch angle of the agricultural implement. The controlsystem is configured to receive the signal indicative of the implementpitch angle from the sensor, determine whether the pitch angle is withina pitch angle range, generate a hitch height control signal indicativeof instructions to adjust a hitch actuator if the pitch angle is notwithin the pitch angle range, and communicate the hitch height controlsignal.

In a second embodiment, a system includes an agricultural vehicleincluding a hitch, a hitch actuator, an agricultural implement, and acontrol system. The agricultural implement is coupled to theagricultural vehicle via the hitch, wherein the agricultural implementcomprises a sensor configured to output a signal indicative of animplement pitch angle of the agricultural implement. The control systemis configured to receive the signal indicative of the implement pitchangle from the sensor, determine whether the pitch angle is within apitch angle range, generate a hitch height control signal indicative ofinstructions to adjust the hitch actuator if the pitch angle is notwithin the pitch angle range, and communicate the hitch height controlsignal to the hitch actuator.

In a third embodiment, a method includes receiving a signal indicativeof an implement pitch angle from a sensor, determining whether the pitchangle is within a pitch angle range, generating a hitch height controlsignal indicative of instructions to adjust a hitch actuator if thepitch angle is not within the pitch angle range, and communicating thehitch height control signal.

DRAWINGS

These and other features, aspects, and advantages of the presentdisclosure will become better understood when the following detaileddescription is read with reference to the accompanying drawings in whichlike characters represent like parts throughout the drawings, wherein:

FIG. 1 is a schematic side view of one embodiment of an implementcoupled to an agricultural vehicle in a fully mounted configuration;

FIG. 2 is a schematic side view of one embodiment of the implementcoupled to the agricultural vehicle in a semi-mounted configuration;

FIG. 3 is a schematic side view of one embodiment of the implementcoupled to the agricultural vehicle via a scissor hitch;

FIG. 4 is a perspective view of one embodiment of an implement that maybe coupled to the agricultural vehicle of FIG. 1;

FIG. 5 is a schematic view of one embodiment of an implement controllerand tractor controller in communication with one another;

FIG. 6 is a simplified schematic view of one embodiment of theimplement, illustrating implement height, hitch height, implement pitchangle, and implement tow length; and

FIG. 7 is a flow chart of an embodiment of a process for leveling anagricultural implement.

DETAILED DESCRIPTION

One or more specific embodiments of the present disclosure will bedescribed below. In an effort to provide a concise description of theseembodiments, all features of an actual implementation may not bedescribed in the specification. It should be appreciated that in thedevelopment of any such actual implementation, as in any engineering ordesign project, numerous implementation-specific decisions must be madeto achieve the developers' specific goals, such as compliance withsystem-related and business-related constraints, which may vary from oneimplementation to another. Moreover, it should be appreciated that sucha development effort might be complex and time consuming, but wouldnevertheless be a routine undertaking of design, fabrication, andmanufacture for those of ordinary skill having the benefit of thisdisclosure.

When introducing elements of various embodiments of the presentdisclosure, the articles “a,” “an,” “the,” and “said” are intended tomean that there are one or more of the elements. The terms “comprising,”“including,” and “having” are intended to be inclusive and mean thatthere may be additional elements other than the listed elements. Anyexamples of operating parameters and/or environmental conditions are notexclusive of other parameters/conditions of the disclosed embodiments.

A tractor may tow or support an implement and move the implement througha field to perform and agricultural task. For some agricultural tasks,the results and/or efficiency of the task may be improved when theimplement is maintained in a level orientation (e.g., at a zero pitchangle relative to the field) or at a desired pitch angle relative to thefield during performance of the agricultural task. Typically, theimplement pitch angle is manually adjusted by the operator (e.g., priorto initialization of the task and/or periodically throughout the task).However, the implement pitch may drift out of the desired implementpitch angle range (e.g., as a result of changing field conditions and/ora reduction in the load carried by the implement 12 as product isdistributed throughout the field). By utilizing a communication linkthat enables the implement to provide control signals to the tractor andan inclinometer coupled to the implement, a height of the tractor hitchmay be adjusted, thereby maintaining the implement at a desired pitchangle during performance of the agricultural task. The implement may becoupled to the tractor via a fully mounted configuration, a semi-mountedconfiguration, or via a scissor hitch.

FIG. 1 is a schematic side view of an embodiment of an implement 12coupled to an agricultural vehicle 10 in a fully mounted configuration.Though the embodiment shown in FIG. 1 includes an agricultural vehicle,such as the illustrated tractor 10, coupled to an implement 12, itshould be understood that some embodiments may include multipleimplements 12. Both the tractor 10 and the implement 12 may be ISOBUSClass 3 compliant, or may communicate with one another via some othercommunication protocol. The implement 12 may be a raker, tillageimplement, mower, planter, seeder, harvester, or any other suitableimplement. In the illustrated embodiment, the implement 12 is coupled tothe tractor 10 by a hitch 14 (e.g., a three-point hitch) in afully-mounted configuration. In other embodiments, the implement 12 maybe mounted directly to the vehicle 10, rather than towed behind thevehicle 10 via the hitch 14. In the illustrated embodiment, the hitch 14is a three-point hitch, however, in other embodiments, the hitch 14 maybe a 2-point hitch, a drawbar hitch, a scissor hitch, or any othersuitable type of hitch. The tractor 10 may include one or more actuators(e.g., cylinder 16) that control the tilt of the hitch 14, or theposition of the hitch links. Similarly, the towed implement 12 mayinclude one or more actuators (e.g., cylinder 18) that control a heightof a portion of the implement 12. Each of the actuators 16, 18 may becontrolled via a hydraulic valve assembly (see FIG. 5) on the tractor10, in fluid communication with the actuators 16, 18 via a series ofhydraulic lines. The implement 12 also includes a sensor (e.g.,inclinometer 20) to determine a pitch angle and/or height of theimplement 12. Based on a distance 22 between the hitch 14 and the gaugewheels 24 (or other ground-engaging component), the actuators 16, 18 maybe adjusted to achieve a desired implement 12 height and pitch angle. Asdescribed in more detail below, the implement 12 controller or controlsystem may use the sensor (e.g., inclinometer 20) to determine theheight and/or pitch angle of the implement 12. If the height and/orpitch angle of the implement 12 are not at the desired height or pitchangle, the implement 12 may then automatically request (e.g., via ISOBUSClass 3 communication with the tractor 10) that the tractor 10controller or control system adjust the height of the hitch 14 and/orthe implement 12 via the one or more actuators 16, 18.

As shown, the three-point hitch 14 includes two lower links 26 and oneupper link 28, each having actuators 16 for adjusting the position ofthe links 26, 28. The implement 12 is coupled to the hitch 14 in a fullymounted configuration, meaning that the implement is coupled to thelower links 26 and the upper link 28. Extending or contracting the hitchactuators 16 may change the position of the links 26, 28, therebycontrolling the hitch 14 height, the height of the implement 12, and/orthe pitch angle of the implement 12. Typically, the lower links 26 areused to control the depth of the implement using the tractor's built inhydraulic cylinders 16, however, the implement may be equipped with amanual or hydraulically controlled gauge wheel 24 and one or moreactuators 18 to control the depth of the implement 12.

FIG. 2 is a schematic side view of one embodiment of the implement 12coupled to the agricultural vehicle 10 in a semi-mounted configuration.As illustrated, the implement 12 is coupled to the two lower links 26 ofthe three-point hitch 14, but not the top link 28. In a semi-mountedconfiguration, lower links 26 may be articulated using the one or moreactuators 16 along with carrying wheel 24 and actuator 18 to controlhitch height and implement 12 pitch angle. The implement 12 controlleror control system may use the sensor (e.g., inclinometer 20) todetermine the height and/or pitch angle of the implement 12. Based onthe distance 22 between the hitch 14 and the gauge wheels 24 (or otherground-engaging component), the actuators 16, 18 may be adjusted toachieve a desired implement 12 height and pitch angle.

FIG. 3 is a schematic side view of one embodiment of the implement 12coupled to the agricultural vehicle 10 via a scissor hitch 48. In thescissor hitch configuration, the implement 12 couples to the vehicle 10via a fixed drawbar 50 and a pin. In the illustrated embodiment, thevehicle 10 may or may not have a three-point hitch in addition to thefixed drawbar 50. Unlike the previously discussed embodiments, the fixeddrawbar 50 has a fixed position relative to the vehicle 10 and may notinclude any actuators. The scissor hitch 48 includes an arm 52 and anactuator 54 (e.g., a cylinder). As the actuator 54 extends or contracts,one or more links 56 coupling the implement 12 to the hitch 48, movingthe arm 52 relative to the rest of the hitch 48, resulting in anadjustment in implement height and pitch angle. As with the previouslydescribed embodiments, the implement 12 height and pitch angle may beadjusted using the actuators 18, 54. The implement 12 controller orcontrol system may use the sensor (e.g., inclinometer 20) to determinethe height and/or pitch angle of the implement 12. Based on the distance22 between the fixed drawbar 50 and the gauge wheels 24 (or otherground-engaging component), the actuators 18, 54 may be adjusted toachieve a desired implement 12 height and pitch angle.

FIG. 4 is a perspective view of one embodiment of an implement 12 thatmay be coupled to the tractor 10 of FIGS. 1-3. In the illustratedembodiment, the implement 12 includes an implement frame 100. Arockshaft 102 extends across the implement frame 100. The rockshaft 102may be supported by bearings at either lateral end, which enable therockshaft 102 to rotate relative to the implement frame 100. Pivotingwheel assemblies 104 are coupled to the rockshaft 102. Thus, as therockshaft 102 rotates, the wheel assemblies 104 raise and lower relativeto the implement frame 100, thereby adjusting the height of the frame atthe rockshaft 102 relative to the field. Actuators (e.g., cylinders 18)are coupled between brackets 106 on the rockshaft 102 and brackets 108on the implement frame 100 such that as the cylinders 18 extend, thewheel assemblies 104 pivot downwardly, raising the height of the frame100 at the rockshaft 102. Similarly, when the cylinders 18 retract, thewheel assemblies 104 pivot upwardly, lowering the height of theimplement 12 frame 100 at the rockshaft 102. The cylinders 18 on theimplement 12 may be used in cooperation with the hitch cylinders 16, 54to adjust the pitch angle and/or the height of the implement 12.

Though the implement 12 shown in FIG. 4 has two wheel assemblies 104 andtwo cylinders 18, it should be understood that that implement 12 ismerely an example and that the implement 12 may have a different numberof wheel assemblies 104 and cylinders 18. For example, the implement 12may have a central frame with two or more cylinders 108 and wheelassemblies 104, as well as one or more wing frames on either side, eachhaving additional cylinders 18 and wheel assemblies 104. In someembodiments, the implement 12 may include multiple rows of wheelassemblies 104, such that cylinders 18 for different rows of wheelassemblies 104 may be set to different positions to control the heightand pitch angle of the implement frame 100. The wheel assemblies 104 mayalso be arranged in locations other than those shown in FIG. 4.Similarly, the implement 12 may utilize other types of wheel assemblies104 than those shown, or may utilize other types of actuators in placeof the cylinders 18. Indeed, the implement 12 may include other systemsfor controlling the height of the implement 12 beyond the rockshaft 102system shown in FIG. 4.

Additionally, some embodiments may include “carried” implements that donot have wheel assemblies. In such embodiments, the implement height 300may be adjusted by a cylinder and linkage coupled to the hitch.

FIG. 5 is a schematic view of one embodiment of an implement controller200 (e.g., ECU) and a tractor controller 202 (e.g., ECU), which may becollectively referred to as a control system, in communication with oneanother. Each of the illustrated implement controller 200 and thetractor controller 202 include a processor 204, a memory component 206,and communication circuitry 208. Each processor 204 may include one ormore general-purpose processors, one or more application specificintegrated circuits, one or more field programmable gate arrays, or thelike. Each memory component 206 may be any tangible, non-transitory,computer readable medium that is capable of storing instructionsexecutable by the respective processor 204 and/or data that may beprocessed by the respective processor 204. In other words, the memory206 may include volatile memory, such as random access memory, ornon-volatile memory, such as hard disk drives, read-only memory, opticaldisks, flash memory, and the like. The communication circuitry 208 maybe configured to receive inputs (e.g., from the other controller 200,202, the inclinometer 20, other sensors, etc.) and to transmit outputs(e.g., control signals, command signals, etc.) to the various componentsof the system (e.g., valve assemblies, the other controller 200, 202,etc.).

The tractor controller 202 may be communicatively coupled to a valveassembly 218 and fluid supply 222 on the tractor. Based on controlsignals from the tractor controller 202 (which may be received from theimplement controller 200), the valve assembly 218 may restrict or enablefluid flow from the fluid supply 222 into the respective cylinders 16,18, 54 via one or more hydraulic lines 216, which may run throughout thevehicle 10 and across to the implement 12. As fluid flows into thecylinders 16, 18, 54, the pressure in the cylinders increases, causingthe cylinders to extend. Correspondingly, as fluid flows out of thecylinders 16, 18, 54, the pressure in the cylinders decreases, causingthe cylinders to contract. The one or more hitch cylinders 16, 54 andthe valve assembly 218 may be collectively referred to as the hitchheight actuator. Similarly, the one or more implement cylinders 18 andthe valve assembly 218 may be collectively referred to as the implementheight actuator.

The implement controller 200 may receive signals indicative of theimplement pitch angle from the sensor 20 (e.g., inclinometer). In theillustrated embodiment, the inclinometer 20 may output a signalindicative of the implement pitch angle to the implement controller 200.In other embodiments, the implement pitch angle may be determined usinganother type of sensor (e.g., gyroscope, sonar, etc.). In furtherembodiments, the pitch angle may be determined by smart cylinders 18, orskis with angle feedback relative to the implement frame. The implement12 height may be determined by the implement controller 200 based on theposition of the cylinders 18, proximity sensors, sonar, or by some othertechnique. The implement controller 200 may then execute a programstored in the memory component 206 via the processor 204 to determinewhether the implement 12 height and pitch angle are within the desiredranges. If the implement controller 200 determines that the heightand/or pitch angle is outside of the desired range, the implementcontroller 200 may generate a control signal indicative of instructionsto control the valve assembly 218, thus extending or contracting theactuators 16, 18, 54, increasing or decreasing the height and/or thepitch angle of the hitch 14 and/or implement 12. The control signal maythen be communicated via a communication protocol (e.g., ISOBUS Class 3)to the tractor controller 202, which communicated the control signal tothe valve assembly 218 to adjust the actuators 16, 18, 54 (e.g., via thehydraulic lines 216) to achieve the desired implement 12 height andpitch angle.

The implement controller 200 and the tractor controller 202 maycommunicate via wired or wireless communication. For example, when theimplement 12 is coupled to the tractor 10, an ISOBUS Class 3 cable 210may connect the tractor controller 202 and the implement controller 200,facilitating communication between the implement controller 200 and thetractor controller 202. The ISOBUS Class 3 cable 210 may have a plug 212that interfaces with a receptacle 214 on the tractor 10. The implementcontroller 200 may provide information to the tractor controller 202 viathe ISOBUS Class 3 cable 210. For example, the implement controller 200may identify the implement 12 (e.g., by type, model number, serialnumber, etc.) or otherwise provide information about its operation viathe ISOBUS Class 3 cable 210. The implement controller 200 may alsocommunicate command signals to the tractor controller 202 via the ISOBUSClass 3 communication connection. For example, based on the pitch angleof the implement 12, the distance between the hitch 14 or fixed drawbar50 and the implement wheels, the desired implement pitch angle, and thedesired implement height, the implement controller 200 may generate acommand signal indicative of instructions to extend or contract theactuators 16, 18, 54 (e.g., via the valve assembly 218) such that thehitch positions an end of the implement proximate to the hitch at adesired height to attain a desired implement pitch angle and/orimplement height. In some embodiments, the desired pitch may be parallelto the field over which and the implement is towed. In otherembodiments, the desired pitch may be parallel to the tractor 10. Infurther embodiments, specific non-zero pitch angles may be desired.Similarly, specific desired implement heights may be set for transport(e.g., driving down a road to a field), when the implement 12 is engaged(e.g., in field work), and when the implement 12 is disengaged (e.g.,out of field work or for implement service).

FIG. 6 is a simplified schematic view of one embodiment of the implement12 illustrating implement height 300, hitch height 302, implement pitchangle 304, and implement tow length 22. The implement height 300 may bedefined as the vertical distance from the ground 308 (e.g., soilsurface) at a point on the implement 12. Though the embodimentillustrated in FIG. 6 shows the implement height 300 as the distancebetween the ground 308 and a point at the top of the implement 12directly above the wheels 24, it should be understood that this ismerely for illustrative purposes and that the implement height 300 maybe determined at any suitable point on the implement 12. The implementheight 300 at the rockshaft may be controlled based upon the position ofthe implement cylinder and/or the position of the hitch cylinder.

The hitch height 302 may be defined as the distance between the ground308 and a portion of the implement 12 that contacts the hitch 14 (orfixed drawbar) of the tractor 10. As with the implement height 300, thehitch height 302 shown in FIG. 6 is merely for illustrative purposes,and it should be understood that the hitch height 302 may be determinedat any suitable point on the tractor or implement 12. The hitch height302 may be controlled based upon the position of the hitch cylinder.

The implement pitch angle 304 may be defined as the angle of theimplement 12 relative to the ground 308 (e.g., ground plane), orrelative to the tractor (e.g., horizontal plane through the tractor).Though in the simplified schematic of the implement 12 in FIG. 6, theimplement pitch angle 304 is zero, or near zero, when the implementheight 300 and the hitch height 302 are equal, it should be understoodthat in some embodiments, when the implement pitch angle 304 is zero,the implement height 300 and the hitch height 302 may be differentvalues. In the illustrated embodiment, the implement pitch angle 304 maybe determined via a sensor 20 (e.g., an inclinometer) mounted on theimplement 12. However, the implement pitch angle 304 may be measured byother types of sensors, or determined in some other way via gyroscope,sonar, proximity sensors, smart cylinders, etc.

The tow length 22 may be defined as a longitudinal distance in theimplement frame of reference between a point where the hitch 14 (orfixed draw bar) contacts the implement 12 and the implement wheels 24.The tow length 22 may be a known value (e.g., stored in the memorycomponent of the implement controller). In some embodiments, the towlength 22 may be communicated from the implement controller to thetractor controller via the ISOBUS Class 3 cable. Using the known towlength 22, the measured implement pitch angle 304 and/or the measuredimplement height 300, the implement controller may determine how muchthe cylinders should extend or contract to achieve the desired implementheight 300 and/or implement pitch angle 304. The implement controllermay generate a control signal indicative of instructions to extend orcontract the cylinders a determined amount to achieve the desiredcylinder positions based on the desired implement pitch angle 304 andimplement height 300. The control signal may be communicated to thetractor controller via the ISOBUS Class 3 cable. The tractor controllermay then communicate instructions (e.g., via control signals) to the oneor more actuators (e.g., valve assembly and cylinders) to extend orcontract the cylinders a given amount.

FIG. 7 is a flow chart for an embodiment of a process 400 for levelingan agricultural implement. The process 400 may be stored in anon-transitory computer readable medium, such as the memory component(e.g., in the form of code), and executable by the processor. In block402, the implement pitch angle and/or the implement height, orparameters indicative of the implement pitch angle and/or the implementheight, are received (e.g., from one or more sensors). The implementpitch angle and/or implement height may be measured or determined in avariety of ways (e.g., inclinometer, gyroscope, sonar, proximitysensors, smart cylinders, etc.).

In decision block 404, the measured implement height is compared to thedesired value or range of values for the implement height. The desiredimplement height, value, or range of values, may be stored in the memorycomponent along with other implement information. The desired range maybe expressed in numbers (e.g., between 46 and 48 inches), or as adesired value with a percentage range (e.g., 48 inches ±2%). In someembodiments, there may be a threshold time period before the measuredimplement height is determined to be outside of the desired range. Forexample, the measured implement height may not be determined to beoutside of the desirable range unless it remains outside of thedesirable range for more than a threshold period of time (e.g., 0.5seconds, 1 second, 1.5 second, 2 seconds, 3 seconds, 4 seconds, 5seconds, etc.). Use of the threshold time period may help to reduce thepossibility of moving the implement in response to noise (e.g., due torough ground, clods of dirt, divots, etc.).

If the implement height is within the desired range, the process 400proceeds to block 414 and monitors the implement pitch angle. If theimplement height is outside of the desired range, the process 400proceeds to block 406. In block 406, the process generates an actuatorcontrol signal indicative of instructions to extend or contract thehitch and/or implement cylinders to the appropriate position for thedesired implement height and implement pitch angle to be attained. Theextension or contraction of the implement cylinder may be based at leastin part upon the measured implement height, the measured implement pitchangle, the tow length of the implement, and the ratio of cylinder stroketo implement frame height adjustment. Because each of the cylinders maybe mounted at angles, and/or coupled by linkages, a length of thecylinder stroke may not result in an equal change in the implement frameheight at the wheels. Accordingly, the relationship between theimplement cylinder position (e.g., extension/contraction) and theimplement frame height at the wheels may be determined. The relationshipmay be stored as a ratio, a look up table, an equation, etc. Oncedesired positions of the hitch cylinders and implement cylinders aredetermined, the control signal is generated indicative of instructionsto extend or contract the one or more hitch cylinders and/or implementcylinders the appropriate amount to achieve the cylinder positions thatcorrespond to the desired implement height and implement pitch angle.

In block 408, the control signal is communicated to the tractorcontroller. In block 410, the control signal is communicated to thevalve assembly. In block 412, the actuators are adjusted in accordancewith the control signal.

In decision block 414, the measured implement pitch angle is compared tothe desired value or range of values for the implement pitch angle. Thedesired implement pitch angle value or range of values may be stored inthe memory component along with other implement information. The desiredrange may be expressed in numbers (e.g., between −5 degrees and 5degrees), or as a desired value with a percentage range (e.g., 5 degrees±2%). In some embodiments, the desired implement pitch angle may bezero. In other embodiments, the desired implement pitch angle may benon-zero. In some embodiments, there may be a threshold time periodbefore the measured implement pitch angle is determined to be outside ofthe desired range. For example, the measured implement pitch angle maynot be determined to be outside of the desirable range unless it remainsoutside of the desirable range for more than a threshold period of time(e.g., 0.5 seconds, 1 second, 1.5 second, 2 seconds, 3 seconds, 4seconds, 5 seconds, etc.). Use of the threshold time period may help toreduce the possibility of moving the implement in response to noise(e.g., due to rough ground, clods of dirt, divots, etc.).

If the implement pitch angle is within the desired range, the process400 returns to block 402, monitoring the measured implement height andimplement pitch angle. If the measured implement pitch angle is outsideof the desired range, the process 400 proceeds to the sequence of blocks406 through 412. As described above, in block 406, an actuator controlsignal is generated. In block 408, the control signal is communicated tothe tractor controller. In block 410, the control signal is communicatedto the valve assembly. In block 412, the actuators are adjusted toachieve the designed desired implement height and/or pitch angle.

In some embodiments, the implement height and implement pitch angle maybe predictively adjusted. For example, the tractor may be equipped witha sensor to determine the height and pitch angle of the tractor as ittraverses an incline or a decline. Based at least in part on the speedof the tractor, the cylinders may be extended or contracted to maintaina desired implement height or implement pitch angle. Similarly, thecylinders may be extended or contracted to maintain a desired implementheight or implement pitch angle based on a topographic map of theterrain being covered.

Though presently disclosed embodiments monitor implement pitch angleduring operation of the implement, it should be understood that thedisclosed techniques may also be used to control the pitch angle of theimplement during a transport mode (e.g., while moving on a road) and/orin a service mode (e.g., while the implement is stationary duringmaintenance, repair, servicing, or component adjustment). Additionally,similar techniques may be used to control the roll angle of theimplement.

The disclosed techniques utilize a communication protocol (e.g., ISOBUSclass 3) between the implement and the tractor, as well as the sensormounted to the implement to monitor the implement pitch angle, andcommunicate a control signal from the implement to the tractorindicative of instructions to adjust the hitch height. By automaticallymonitoring and maintaining the implement pitch angle at a desired value,the pitch angle of the implement may remain within a desired rangeduring operation of the implement, thus increasing the performanceand/or efficiency of the implement during performance of theagricultural task.

While only certain features of the disclosure have been illustrated anddescribed herein, many modifications and changes will occur to thoseskilled in the art. It is, therefore, to be understood that the appendedclaims are intended to cover all such modifications and changes as fallwithin the true spirit of the disclosure.

What is claimed is:
 1. A system, comprising: an agricultural implementconfigured to be coupled to an agricultural vehicle; a sensor coupled tothe agricultural implement and configured to output a signal indicativeof a pitch angle of the agricultural implement; and a control systemconfigured to: receive the signal indicative of the pitch angle from thesensor; determine whether the pitch angle is within a pitch angle range;generate a hitch height control signal indicative of instructions toadjust a hitch actuator if the pitch angle is not within the pitch anglerange; and communicate the hitch height control signal.
 2. The system ofclaim 1, wherein the control system comprises an implement controller,wherein the implement controller is configured to communicate the hitchheight control signal to a tractor controller.
 3. The system of claim 1,wherein the agricultural implement comprises a plurality of wheelassemblies.
 4. The system of claim 3, wherein the hitch height controlsignal is based, at least in part, on the pitch angle, and a distancebetween an implement frame and the wheel assemblies of the implement. 5.The system of claim 4, wherein the hitch height control signal is based,at least in part, on a relationship between a hitch height cylinderposition and a hitch height.
 6. The system of claim 3, comprising animplement actuator comprising an implement cylinder coupled between oneor more of the plurality of wheel assemblies and a frame of theagricultural implement, wherein an implement cylinder positioncorresponds to an implement frame height.
 7. The system of claim 6,wherein the control system is configured to: determine the implementcylinder position that corresponds to a desired implement height;generate an implement height control signal indicative of instructionsto extend or contract the plurality of implement cylinders to theimplement cylinder position; and communicate the implement heightcontrol signal to a valve assembly that restricts or enables fluid flowbetween a fluid supply and the implement cylinder based at least in parton the implement height control signal.
 8. The system of claim 7,wherein the implement height control signal is based, at least in part,on a relationship between the implement cylinder position and theimplement frame height.
 9. The system of claim 1, comprising an ISOBUSClass 3 cable configured to plug into a tractor and communicativelycouple the implement controller and the tractor controller.
 10. Thesystem of claim 1, wherein the hitch height control signal iscommunicated via ISOBUS Class 3 communication protocol.
 11. A system,comprising: an agricultural vehicle, comprising a hitch; a hitchactuator configured to adjust a hitch height; an agricultural implementcoupled to the agricultural vehicle via the hitch, wherein theagricultural implement comprises a sensor configured to output a signalindicative of an implement pitch angle of the agricultural implement;and a control system configured to: receive the signal indicative of theimplement pitch angle from the sensor; determine whether the pitch angleis within a pitch angle range; generate a hitch height control signalindicative of instructions to adjust the hitch actuator if the pitchangle is not within the pitch angle range; and communicate the hitchheight control signal to the hitch actuator.
 12. The system of claim 11,wherein hitch actuator comprises a cylinder configured to extend orcontract to increase or decrease the hitch height, and a valve assemblyconfigured to restrict or enable fluid flow between a fluid supply andthe cylinder, causing the cylinder to extend or contract.
 13. The systemof claim 12, wherein the control system comprises an implementcontroller and a tractor controller, wherein the implement controller isconfigured to communicate the hitch height control signal to the tractorcontroller.
 14. The system of claim 13, wherein the implement controlleris disposed within the implement, the tractor controller is disposedwithin the tractor, and wherein the implement controller and the tractorcontroller communicate with one another via an ISOBUS Class 3communication protocol.
 15. The system of claim 14, wherein the valveassembly restricts or enables fluid flow between the fluid supply andthe cylinder based at least in part on the hitch height control signal.16. The system of claim 15, wherein the agricultural implementcomprises: an implement frame; a plurality of wheel assemblies; and animplement height actuator configured to adjust an implement height byincreasing or decreasing a distance between the implement frame and thewheel assemblies.
 17. The system of claim 16, wherein the control systemis configured to: receive a signal indicative of the implement heightfrom the sensor; determine whether the implement height is within animplement height range; generate a first and a second control signalindicative of instructions to adjust the hitch height actuator and theimplement height actuator, respectively, if the implement height is notwithin the implement height range; communicate the first control signalto the hitch height actuator; and communicate the second control signalto the implement height actuator.